This application claims priority of Taiwan patent Application No. 90205362, filed on Apr. 6, 2001.
1. Field of the Invention
This invention relates to a treadmill that includes a treadbase and a supporting unit that supports the treadbase in a folded position.
2. Description of the Related Art
FIGS. 1 to 3 illustrate a conventional treadmill that includes a base frame 1, a treadbase 2 disposed above the base frame 1, and a supporting unit 3 disposed between the base frame 1 and the treadbase 2. The treadbase 2 is pivoted to the supporting unit 3 so as to be turnable about an axis between horizontal and folded positions relative to the base frame 1. The supporting unit 3 includes front and rear legs 103, 104 which are pivoted to the treadbase 2 via pivot pins that define the aforesaid axis. An inclination member includes a motor 303 mounted on a front end of the base frame 1, and an adjusting tubular member 4 which has a tubular sleeve 301 connected to the rear legs 104 and a screw rod 302 threadedly engaging the sleeve 301 and connected to the motor 303 so as to move the rear legs 104 toward the front legs 103 via movement of the sleeve 301, which, in turn, raises a front end of the treadbase 2 upwardly, thereby inclining the treadbase 2 relative to the base frame 1.
The conventional treadmill is disadvantageous in that in order to avoid interference with the base frame 1, the front end of the treadbase 2 has to be raised prior to the rotation of the treadbase 2 to the folded position, which results in inconvenience.
Therefore, it is an object of the present invention to provide a treadmill that is capable of overcoming the aforementioned drawbacks.
According to this invention, there is provided a treadmill that comprises: a base frame having front and rear ends; a treadbase disposed above the base frame, and having front and rear ends, left and right walls extending in a longitudinal direction from the front end to the rear end, and a first crossbar interconnecting the left and right walls; and a supporting unit that is disposed between the treadbase and the base frame and that includes spaced apart left and right rear legs which project upwardly and frontwardly from the rear end of the base frame to the treadbase and which have front ends pivoted to the front end of the treadbase anterior to the first crossbar so as to permit the treadbase to be turnable about a first axis that extends in a transverse direction relative to the longitudinal direction, and rear ends pivoted to the rear end of the base frame so as to permit the left and right rear legs to be turnable about a second axis that is parallel to the first axis, the treadbase being turnable about the first axis between a horizontal position, in which the treadbase lies on the base frame, and a folded position, in which the treadbase projects uprightly from the base frame, the supporting unit further including a second crossbar which interconnects the left and right rear legs and which is disposed between the first and second axes, and a hydraulic cylinder which includes a cylinder body pivoted to the second crossbar so as to permit the hydraulic cylinder to be turnable about a third axis that is parallel to the first axis, and a retractable piston projecting movably from the cylinder body and having a distal end which is distal from the cylinder body and which is connected to the first crossbar so that when the treadbase is turned from the horizontal position to the folded position, the piston of the hydraulic cylinder will be pulled to an extended state and the hydraulic cylinder will be turned so as to extend in a direction substantially perpendicular to the base frame in order to support the treadbase which leans inclinedly against the distal end of the piston of the hydraulic cylinder, and the left and right rear legs will be turned upwardly and rearwardly via pulling action of the hydraulic cylinder, which results in lifting of the first axis together with the front end of the treadbase that is turning toward the base frame.